Combine the oyster sauce, soy sauce, fish sauce, and sugar in a mixing bowl. Whisk it well until the sugar is dissolved and set it aside.

In a wok or large skillet, heat the oil over medium heat.

Add the julienned onions and sauté until they become soft and translucent, about 5 minutes. To speed things up, add a splash of water and cover the pan until it steams for a minute and then uncover to cook until all the water evaporates.

Once the onions are softened, stir in the chopped garlic and chilies, cooking until the garlic turns golden brown—be careful not to burn it!

Pour in approximately 3/4 cup of the stock along with your prepared sauce mixture and a generous grind of black or white pepper. Stir until combined. If desired, add a dash of dark soy sauce for color.

Toss in the julienned red bell pepper and cook for about a minute until just tender.

Turn off the heat and stir in the basil leaves just until they wilt.

Taste your sauce; if it’s too salty, dilute it with a little more stock or water.

Use the sauce right away in stir-fried dishes, or let it cool and store in the refrigerator for up to a week.